1. Subject Area
This invention relates to improvements in the straightening of rigid frames and sheet metal surfaces, such as frames, bodies and doors of a vehicle and, more particularly, apparatus for the straightening thereof by the simultaneous application of multi-directional forces exerted by power devices.
2. Prior Art
The straightening of vehicle frames and sheet metal products by mechanical means is well known and has been practiced for many years as, for example, is reflected in U.S. Pat. No. 3,492,855 (1970) to Wylie; U.S. Pat. No. 3,796,084 (1974) to Jarman; U.S. Pat. No. 3,506,777 (1975) to Dickens; U.S. Pat. No. 4,257,255 (1981) to Sanchez; and U.S. Pat. No. 4,658,629 (1987) to Grace. A typical prior art structure is shown in FIG. 1.
Generally, frame-straightening systems are extremely bulky, require considerable space to operate, and represent a high capital cost to a body shop or other establishment. Also, the precision of operation of such machines, particularly when multi-directional forces would be useful in addressing a given straightening job, is lacking because it is difficult to control the forces applied by such machines, and it is also difficult to apply multi-directional components of pulling force to the workpiece.
In view of the above limitations of such conventional, heavy, large and imprecise frame and sheet metal straightening systems, it has been difficult to repair automobiles of the past which, typically, made use of a semi-rigid body or shell segments placed over a rigid frame. Nonetheless, the prior art is more suitable to the repair of such automobiles because vehicle manufacturers then employed large tolerances between body panels. However, with the advent of modern manufacturing techniques, most vehicles now produced are of a uni-body type construction, in which the frame component is largely eliminated by a tight integration, at low tolerance, of several smaller semi-rigid sub-assemblies. This low tolerance integration causes an entire vehicle, not simply the impacted area, to distort upon a collision, thereby magnifying the damage and cost of repair in the event of an accident. Furthermore, the strength and rigidity of uni-body vehicles are highly dependent on the above referenced close tolerances between the constituent sub-assemblies. Therein, body shop professionals are now aware that prior art straightening machines lack the ability to apply and regulate small movements, as well as to control the directionality thereof, required to repair the body of such modern vehicles.
Responsive thereto, the within inventor has developed a system capable of effecting small controlled movements of a powerful apparatus that, when physically anchored to a vehicle to be repaired, permits the operator to controllably restore the normal dimension and curvature of damaged uni-body segments. Such small controlled movements are made possible through the elimination of the use of chains, as are common in the prior art (see for example Grace, U.S. Pat. No. 4,658,628 above). Furthermore, the elimination of the chain in a straightening apparatus, as is further set forth below, renders it possible to impart pulling forces in multiple directions, that is, not simply to apply a linear pulling force. Because of this, an operator of the present system can combine multiple prior art movements into a single movement that would otherwise have required multiple operations.
In addition to the particular application of the present invention to present day small tolerance uni-body vehicles, the time of repair of vehicles, regardless of vintage, is substantially decreased.
The present invention relates to a vehicle frame straightening system including a rigid vertical post secured to rigid base; a circumferential post sleeve slidably mounted about an upper segment of said post; and an elongate pulling member including frame engagement means at one end thereof. The system also includes a circumferential sleeve slidably mounted about a central segment of said pulling member, said sleeve having a frame-opposing end and a frame-distal end. An axle is transverely mounted upon said post sleeve to which is pivotally secured said pulling member sleeve. Further included in the system is first linear position actuation means (LPPAM) pivotally mounted to said first sleeve above said axle, said first LPPAM having a drive end and a driven end, said driven end pivotally spool-coupled to said frame-opposing end of said pulling member sleeve. First and second scissors arms are pivotally coupled to each other at opposing ends thereof in which said first arm is also pivotally secured to said distal end of pulling member and said second arm is pivotally secured to said frame-distal end of said pulling member sleeve. Finally, there is provided a second LPPAM having a drive end and a drive end which is secured transversely between said scissors arms. Said drive end is spool-coupled to said first arm and said driven end is coupled in a linear incremental advance relationship to said second arm. Resultantly, selected actuation of said first LPPAM rotatably calibrates the angle of action of said elongate pulling member on the vehicle frame. Selectable actuation of said second LPPAM effects incremental linear pulling of said pulling member inclusive of said frame engagement means thereof. Each of said LPPAM preferably comprises a screw and worm gear assembly, although hydraulic means may also be used.
It is a primary object of the present invention to provide an improved vehicle body and frame-straightening apparatus particularly adapted for use with low tolerance uni-frame body type vehicles.
It is another object to provide an apparatus of the above type capable of efficiently imparting fine increments of multi-directional forces within a single pulling operation.
It is a further object of the invention to provide an apparatus of the above type that will provide for more efficient, less time consuming vehicle repair.
It is a yet further object to provide a vehicle straightening apparatus of the above type having reduced size, cost and weight as opposed to vehicle frame straightening apparatus that are known in the prior art.
The above and yet other objects and advantages of the invention will become apparent from the hereinafter set forth Brief Description of the Drawings, Detailed Description of the Invention, and claims appended herewith.